PbSe/PbS Core/Shell Nanoplatelets with Enhanced Stability and Photoelectric Properties

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Lead chalcogenide nanoplatelets (NPLs) are promising for near-infrared (IR) and IR spectrum applications.
• Improving the stability and performance of NPLs is crucial for device fabrication.

Purpose of the Study:

• To synthesize PbSe/PbS core/shell NPLs using cation exchange.
• To evaluate the optoelectrical properties and potential of these core/shell NPLs for device applications.

Main Methods:

• Cation exchange method for PbSe/PbS core/shell NPL synthesis.
• Fabrication of a photoconductor device using the synthesized NPLs.
• Carrier transport investigation using field-effect transistor (FET) measurements.

Main Results:

• The PbSe/PbS core/shell NPLs exhibited enhanced colloidal and environmental stability.
• The synthesized NPLs passivated surface trap states while preserving core properties.
• The fabricated photoconductor showed enhanced conductivity and responsivity with a 13 kHz bandwidth.
• Field-effect transistor measurements indicated p-type conductivity with a charge mobility of 1.26 × 10^-2 cm²·V^-1·s^-1.

Conclusions:

• Cation exchange is an effective method for creating stable PbSe/PbS core/shell NPLs.
• These core/shell NPLs demonstrate significant potential for optoelectrical devices due to improved stability and performance.
• The enhanced NPLs offer a viable material for high-performance IR optoelectronics.